// This code is derived from jcifs smb client library <jcifs at samba dot org>
// Ported by J. Arturo <webmaster at komodosoft dot net>
//  
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// 
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
// 
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
using System;
using System.IO;
using SharpCifs.Util;
using SharpCifs.Util.Sharpen;

namespace SharpCifs.Smb
{
    /// <summary>
    /// There are hundreds of error codes that may be returned by a CIFS
    /// server.
    /// </summary>
    /// <remarks>
    /// There are hundreds of error codes that may be returned by a CIFS
    /// server. Rather than represent each with it's own <code>Exception</code>
    /// class, this class represents all of them. For many of the popular
    /// error codes, constants and text messages like "The device is not ready"
    /// are provided.
    /// <p>
    /// The jCIFS client maps DOS error codes to NTSTATUS codes. This means that
    /// the user may recieve a different error from a legacy server than that of
    /// a newer varient such as Windows NT and above. If you should encounter
    /// such a case, please report it to jcifs at samba dot org and we will
    /// change the mapping.
    /// </remarks>

    public class SmbException : IOException
    {

        internal static string GetMessageByCode(int errcode)
        {
            if (errcode == 0)
            {
                return "NT_STATUS_SUCCESS";
            }
            if ((errcode & unchecked((int)(0xC0000000))) == unchecked((int)(0xC0000000)))
            {
                int min = 1;
                int max = NtStatus.NtStatusCodes.Length - 1;
                while (max >= min)
                {
                    int mid = (min + max) / 2;
                    if (errcode > NtStatus.NtStatusCodes[mid])
                    {
                        min = mid + 1;
                    }
                    else
                    {
                        if (errcode < NtStatus.NtStatusCodes[mid])
                        {
                            max = mid - 1;
                        }
                        else
                        {
                            return NtStatus.NtStatusMessages[mid];
                        }
                    }
                }
            }
            else
            {
                int min = 0;
                int max = DosError.DosErrorCodes.Length - 1;
                while (max >= min)
                {
                    int mid = (min + max) / 2;
                    if (errcode > DosError.DosErrorCodes[mid][0])
                    {
                        min = mid + 1;
                    }
                    else
                    {
                        if (errcode < DosError.DosErrorCodes[mid][0])
                        {
                            max = mid - 1;
                        }
                        else
                        {
                            return DosError.DosErrorMessages[mid];
                        }
                    }
                }
            }
            return "0x" + Hexdump.ToHexString(errcode, 8);
        }

        internal static int GetStatusByCode(int errcode)
        {
            if ((errcode & unchecked((int)(0xC0000000))) != 0)
            {
                return errcode;
            }
            int min = 0;
            int max = DosError.DosErrorCodes.Length - 1;
            while (max >= min)
            {
                int mid = (min + max) / 2;
                if (errcode > DosError.DosErrorCodes[mid][0])
                {
                    min = mid + 1;
                }
                else
                {
                    if (errcode < DosError.DosErrorCodes[mid][0])
                    {
                        max = mid - 1;
                    }
                    else
                    {
                        return DosError.DosErrorCodes[mid][1];
                    }
                }
            }
            return NtStatus.NtStatusUnsuccessful;
        }

        internal static string GetMessageByWinerrCode(int errcode)
        {
            int min = 0;
            int max = WinError.WinerrCodes.Length - 1;
            while (max >= min)
            {
                int mid = (min + max) / 2;
                if (errcode > WinError.WinerrCodes[mid])
                {
                    min = mid + 1;
                }
                else
                {
                    if (errcode < WinError.WinerrCodes[mid])
                    {
                        max = mid - 1;
                    }
                    else
                    {
                        return WinError.WinerrMessages[mid];
                    }
                }
            }
            return errcode + string.Empty;
        }

        private int _status;

        private Exception _rootCause;

        public SmbException()
        {
        }

        internal SmbException(int errcode, Exception rootCause)
            : base(GetMessageByCode(errcode), rootCause)
        {
            _status = GetStatusByCode(errcode);
            this._rootCause = rootCause;
        }

        public SmbException(string msg) : base(msg)
        {
            _status = NtStatus.NtStatusUnsuccessful;
        }

        public SmbException(string msg, Exception rootCause) : base(msg, rootCause)
        {
            this._rootCause = rootCause;
            _status = NtStatus.NtStatusUnsuccessful;
        }

        public SmbException(int errcode, bool winerr)
            : base(winerr
                        ? GetMessageByWinerrCode(errcode)
                        : GetMessageByCode(errcode))
        {
            _status = winerr
                        ? errcode
                        : GetStatusByCode(errcode);
        }

        public virtual int GetNtStatus()
        {
            return _status;
        }

        public virtual Exception GetRootCause()
        {
            return _rootCause;
        }

        public override string ToString()
        {
            if (_rootCause != null)
            {
                StringWriter sw = new StringWriter();
                PrintWriter pw = new PrintWriter(sw);
                Runtime.PrintStackTrace(_rootCause, pw);
                return base.ToString() + "\n" + sw;
            }
            return base.ToString();
        }
    }
}
